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  • Committer: Teddy Hogeborn
  • Date: 2008-07-21 04:42:08 UTC
  • mfrom: (15.1.3 mandos)
  • Revision ID: teddy@fukt.bsnet.se-20080721044208-y8v1sjmvalfiehrv
Merge.

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# This program is partly derived from an example program for an Avahi
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# service publisher, downloaded from
8
8
# <http://avahi.org/wiki/PythonPublishExample>.  This includes the
9
 
# methods "add" and "remove" in the "AvahiService" class, the
10
 
# "server_state_changed" and "entry_group_state_changed" functions,
11
 
# and some lines in "main".
 
9
# following functions: "add_service", "remove_service",
 
10
# "server_state_changed", "entry_group_state_changed", and some lines
 
11
# in "main".
12
12
13
 
# Everything else is
14
 
# Copyright © 2007-2008 Teddy Hogeborn & Björn Påhlsson
 
13
# Everything else is Copyright © 2007-2008 Teddy Hogeborn and Björn
 
14
# Påhlsson.
15
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# This program is free software: you can redistribute it and/or modify
17
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# it under the terms of the GNU General Public License as published by
24
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#     GNU General Public License for more details.
25
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# You should have received a copy of the GNU General Public License
27
 
# along with this program.  If not, see
28
 
# <http://www.gnu.org/licenses/>.
 
27
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
29
28
30
 
# Contact the authors at <mandos@fukt.bsnet.se>.
 
29
# Contact the authors at <https://www.fukt.bsnet.se/~belorn/> and
 
30
# <https://www.fukt.bsnet.se/~teddy/>.
31
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33
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from __future__ import division
55
55
import stat
56
56
import logging
57
57
import logging.handlers
58
 
import pwd
59
58
 
60
59
import dbus
61
60
import gobject
63
62
from dbus.mainloop.glib import DBusGMainLoop
64
63
import ctypes
65
64
 
66
 
version = "1.0"
 
65
# Brief description of the operation of this program:
 
66
 
67
# This server announces itself as a Zeroconf service.  Connecting
 
68
# clients use the TLS protocol, with the unusual quirk that this
 
69
# server program acts as a TLS "client" while the connecting clients
 
70
# acts as a TLS "server".  The clients (acting as a TLS "server") must
 
71
# supply an OpenPGP certificate, and the fingerprint of this
 
72
# certificate is used by this server to look up (in a list read from a
 
73
# file at start time) which binary blob to give the client.  No other
 
74
# authentication or authorization is done by this server.
 
75
 
67
76
 
68
77
logger = logging.Logger('mandos')
69
78
syslogger = logging.handlers.SysLogHandler\
70
 
            (facility = logging.handlers.SysLogHandler.LOG_DAEMON,
71
 
             address = "/dev/log")
 
79
            (facility = logging.handlers.SysLogHandler.LOG_DAEMON)
72
80
syslogger.setFormatter(logging.Formatter\
73
 
                        ('Mandos: %(levelname)s: %(message)s'))
 
81
                        ('%(levelname)s: %(message)s'))
74
82
logger.addHandler(syslogger)
75
 
 
76
 
console = logging.StreamHandler()
77
 
console.setFormatter(logging.Formatter('%(name)s: %(levelname)s:'
78
 
                                       ' %(message)s'))
79
 
logger.addHandler(console)
80
 
 
81
 
class AvahiError(Exception):
82
 
    def __init__(self, value):
83
 
        self.value = value
84
 
    def __str__(self):
85
 
        return repr(self.value)
86
 
 
87
 
class AvahiServiceError(AvahiError):
88
 
    pass
89
 
 
90
 
class AvahiGroupError(AvahiError):
91
 
    pass
92
 
 
93
 
 
94
 
class AvahiService(object):
95
 
    """An Avahi (Zeroconf) service.
96
 
    Attributes:
97
 
    interface: integer; avahi.IF_UNSPEC or an interface index.
98
 
               Used to optionally bind to the specified interface.
99
 
    name: string; Example: 'Mandos'
100
 
    type: string; Example: '_mandos._tcp'.
101
 
                  See <http://www.dns-sd.org/ServiceTypes.html>
102
 
    port: integer; what port to announce
103
 
    TXT: list of strings; TXT record for the service
104
 
    domain: string; Domain to publish on, default to .local if empty.
105
 
    host: string; Host to publish records for, default is localhost
106
 
    max_renames: integer; maximum number of renames
107
 
    rename_count: integer; counter so we only rename after collisions
108
 
                  a sensible number of times
109
 
    """
110
 
    def __init__(self, interface = avahi.IF_UNSPEC, name = None,
111
 
                 type = None, port = None, TXT = None, domain = "",
112
 
                 host = "", max_renames = 32768):
113
 
        self.interface = interface
114
 
        self.name = name
115
 
        self.type = type
116
 
        self.port = port
117
 
        if TXT is None:
118
 
            self.TXT = []
119
 
        else:
120
 
            self.TXT = TXT
121
 
        self.domain = domain
122
 
        self.host = host
123
 
        self.rename_count = 0
124
 
        self.max_renames = max_renames
125
 
    def rename(self):
126
 
        """Derived from the Avahi example code"""
127
 
        if self.rename_count >= self.max_renames:
128
 
            logger.critical(u"No suitable Zeroconf service name found"
129
 
                            u" after %i retries, exiting.",
130
 
                            rename_count)
131
 
            raise AvahiServiceError("Too many renames")
132
 
        self.name = server.GetAlternativeServiceName(self.name)
133
 
        logger.info(u"Changing Zeroconf service name to %r ...",
134
 
                    str(self.name))
135
 
        syslogger.setFormatter(logging.Formatter\
136
 
                               ('Mandos (%s): %%(levelname)s:'
137
 
                               ' %%(message)s' % self.name))
138
 
        self.remove()
139
 
        self.add()
140
 
        self.rename_count += 1
141
 
    def remove(self):
142
 
        """Derived from the Avahi example code"""
143
 
        if group is not None:
144
 
            group.Reset()
145
 
    def add(self):
146
 
        """Derived from the Avahi example code"""
147
 
        global group
148
 
        if group is None:
149
 
            group = dbus.Interface\
150
 
                    (bus.get_object(avahi.DBUS_NAME,
151
 
                                    server.EntryGroupNew()),
152
 
                     avahi.DBUS_INTERFACE_ENTRY_GROUP)
153
 
            group.connect_to_signal('StateChanged',
154
 
                                    entry_group_state_changed)
155
 
        logger.debug(u"Adding Zeroconf service '%s' of type '%s' ...",
156
 
                     service.name, service.type)
157
 
        group.AddService(
158
 
                self.interface,         # interface
159
 
                avahi.PROTO_INET6,      # protocol
160
 
                dbus.UInt32(0),         # flags
161
 
                self.name, self.type,
162
 
                self.domain, self.host,
163
 
                dbus.UInt16(self.port),
164
 
                avahi.string_array_to_txt_array(self.TXT))
165
 
        group.Commit()
166
 
 
 
83
del syslogger
 
84
 
 
85
# This variable is used to optionally bind to a specified interface.
 
86
# It is a global variable to fit in with the other variables from the
 
87
# Avahi example code.
 
88
serviceInterface = avahi.IF_UNSPEC
167
89
# From the Avahi example code:
168
 
group = None                            # our entry group
 
90
serviceName = "Mandos"
 
91
serviceType = "_mandos._tcp" # http://www.dns-sd.org/ServiceTypes.html
 
92
servicePort = None                      # Not known at startup
 
93
serviceTXT = []                         # TXT record for the service
 
94
domain = ""                  # Domain to publish on, default to .local
 
95
host = ""          # Host to publish records for, default to localhost
 
96
group = None #our entry group
 
97
rename_count = 12       # Counter so we only rename after collisions a
 
98
                        # sensible number of times
169
99
# End of Avahi example code
170
100
 
171
101
 
176
106
    fingerprint: string (40 or 32 hexadecimal digits); used to
177
107
                 uniquely identify the client
178
108
    secret:    bytestring; sent verbatim (over TLS) to client
179
 
    host:      string; available for use by the checker command
180
 
    created:   datetime.datetime(); object creation, not client host
181
 
    last_checked_ok: datetime.datetime() or None if not yet checked OK
182
 
    timeout:   datetime.timedelta(); How long from last_checked_ok
183
 
                                     until this client is invalid
 
109
    fqdn:      string (FQDN); available for use by the checker command
 
110
    created:   datetime.datetime()
 
111
    last_seen: datetime.datetime() or None if not yet seen
 
112
    timeout:   datetime.timedelta(); How long from last_seen until
 
113
                                     this client is invalid
184
114
    interval:  datetime.timedelta(); How often to start a new checker
185
115
    stop_hook: If set, called by stop() as stop_hook(self)
186
116
    checker:   subprocess.Popen(); a running checker process used
187
117
                                   to see if the client lives.
188
 
                                   'None' if no process is running.
 
118
                                   Is None if no process is running.
189
119
    checker_initiator_tag: a gobject event source tag, or None
190
120
    stop_initiator_tag:    - '' -
191
121
    checker_callback_tag:  - '' -
192
122
    checker_command: string; External command which is run to check if
193
 
                     client lives.  %() expansions are done at
 
123
                     client lives.  %()s expansions are done at
194
124
                     runtime with vars(self) as dict, so that for
195
125
                     instance %(name)s can be used in the command.
196
126
    Private attibutes:
197
127
    _timeout: Real variable for 'timeout'
198
128
    _interval: Real variable for 'interval'
199
 
    _timeout_milliseconds: Used when calling gobject.timeout_add()
 
129
    _timeout_milliseconds: Used by gobject.timeout_add()
200
130
    _interval_milliseconds: - '' -
201
131
    """
202
132
    def _set_timeout(self, timeout):
222
152
    interval = property(lambda self: self._interval,
223
153
                        _set_interval)
224
154
    del _set_interval
225
 
    def __init__(self, name = None, stop_hook=None, config={}):
226
 
        """Note: the 'checker' key in 'config' sets the
227
 
        'checker_command' attribute and *not* the 'checker'
228
 
        attribute."""
 
155
    def __init__(self, name=None, options=None, stop_hook=None,
 
156
                 fingerprint=None, secret=None, secfile=None,
 
157
                 fqdn=None, timeout=None, interval=-1, checker=None):
 
158
        """Note: the 'checker' argument sets the 'checker_command'
 
159
        attribute and not the 'checker' attribute.."""
229
160
        self.name = name
230
 
        logger.debug(u"Creating client %r", self.name)
231
 
        # Uppercase and remove spaces from fingerprint for later
232
 
        # comparison purposes with return value from the fingerprint()
233
 
        # function
234
 
        self.fingerprint = config["fingerprint"].upper()\
235
 
                           .replace(u" ", u"")
236
 
        logger.debug(u"  Fingerprint: %s", self.fingerprint)
237
 
        if "secret" in config:
238
 
            self.secret = config["secret"].decode(u"base64")
239
 
        elif "secfile" in config:
240
 
            sf = open(config["secfile"])
 
161
        # Uppercase and remove spaces from fingerprint
 
162
        # for later comparison purposes with return value of
 
163
        # the fingerprint() function
 
164
        self.fingerprint = fingerprint.upper().replace(u" ", u"")
 
165
        if secret:
 
166
            self.secret = secret.decode(u"base64")
 
167
        elif secfile:
 
168
            sf = open(secfile)
241
169
            self.secret = sf.read()
242
170
            sf.close()
243
171
        else:
244
 
            raise TypeError(u"No secret or secfile for client %s"
245
 
                            % self.name)
246
 
        self.host = config.get("host", "")
 
172
            raise RuntimeError(u"No secret or secfile for client %s"
 
173
                               % self.name)
 
174
        self.fqdn = fqdn                # string
247
175
        self.created = datetime.datetime.now()
248
 
        self.last_checked_ok = None
249
 
        self.timeout = string_to_delta(config["timeout"])
250
 
        self.interval = string_to_delta(config["interval"])
 
176
        self.last_seen = None
 
177
        if timeout is None:
 
178
            self.timeout = options.timeout
 
179
        else:
 
180
            self.timeout = string_to_delta(timeout)
 
181
        if interval == -1:
 
182
            self.interval = options.interval
 
183
        else:
 
184
            self.interval = string_to_delta(interval)
251
185
        self.stop_hook = stop_hook
252
186
        self.checker = None
253
187
        self.checker_initiator_tag = None
254
188
        self.stop_initiator_tag = None
255
189
        self.checker_callback_tag = None
256
 
        self.check_command = config["checker"]
 
190
        self.check_command = checker
257
191
    def start(self):
258
192
        """Start this client's checker and timeout hooks"""
259
193
        # Schedule a new checker to be started an 'interval' from now,
269
203
                                   self.stop)
270
204
    def stop(self):
271
205
        """Stop this client.
272
 
        The possibility that a client might be restarted is left open,
273
 
        but not currently used."""
 
206
        The possibility that this client might be restarted is left
 
207
        open, but not currently used."""
274
208
        # If this client doesn't have a secret, it is already stopped.
275
 
        if hasattr(self, "secret") and self.secret:
276
 
            logger.info(u"Stopping client %s", self.name)
 
209
        if self.secret:
 
210
            logger.debug(u"Stopping client %s", self.name)
277
211
            self.secret = None
278
212
        else:
279
213
            return False
280
 
        if getattr(self, "stop_initiator_tag", False):
 
214
        if hasattr(self, "stop_initiator_tag") \
 
215
               and self.stop_initiator_tag:
281
216
            gobject.source_remove(self.stop_initiator_tag)
282
217
            self.stop_initiator_tag = None
283
 
        if getattr(self, "checker_initiator_tag", False):
 
218
        if hasattr(self, "checker_initiator_tag") \
 
219
               and self.checker_initiator_tag:
284
220
            gobject.source_remove(self.checker_initiator_tag)
285
221
            self.checker_initiator_tag = None
286
222
        self.stop_checker()
298
234
        self.checker = None
299
235
        if os.WIFEXITED(condition) \
300
236
               and (os.WEXITSTATUS(condition) == 0):
301
 
            logger.info(u"Checker for %(name)s succeeded",
302
 
                        vars(self))
303
 
            self.last_checked_ok = now
 
237
            logger.debug(u"Checker for %(name)s succeeded",
 
238
                         vars(self))
 
239
            self.last_seen = now
304
240
            gobject.source_remove(self.stop_initiator_tag)
305
241
            self.stop_initiator_tag = gobject.timeout_add\
306
242
                                      (self._timeout_milliseconds,
309
245
            logger.warning(u"Checker for %(name)s crashed?",
310
246
                           vars(self))
311
247
        else:
312
 
            logger.info(u"Checker for %(name)s failed",
313
 
                        vars(self))
 
248
            logger.debug(u"Checker for %(name)s failed",
 
249
                         vars(self))
314
250
    def start_checker(self):
315
251
        """Start a new checker subprocess if one is not running.
316
252
        If a checker already exists, leave it running and do
325
261
        # is as it should be.
326
262
        if self.checker is None:
327
263
            try:
328
 
                # In case check_command has exactly one % operator
329
 
                command = self.check_command % self.host
 
264
                command = self.check_command % self.fqdn
330
265
            except TypeError:
331
 
                # Escape attributes for the shell
332
266
                escaped_attrs = dict((key, re.escape(str(val)))
333
267
                                     for key, val in
334
268
                                     vars(self).iteritems())
335
269
                try:
336
270
                    command = self.check_command % escaped_attrs
337
271
                except TypeError, error:
338
 
                    logger.error(u'Could not format string "%s":'
339
 
                                 u' %s', self.check_command, error)
 
272
                    logger.critical(u'Could not format string "%s":'
 
273
                                    u' %s', self.check_command, error)
340
274
                    return True # Try again later
341
275
            try:
342
 
                logger.info(u"Starting checker %r for %s",
343
 
                            command, self.name)
344
 
                # We don't need to redirect stdout and stderr, since
345
 
                # in normal mode, that is already done by daemon(),
346
 
                # and in debug mode we don't want to.  (Stdin is
347
 
                # always replaced by /dev/null.)
348
 
                self.checker = subprocess.Popen(command,
349
 
                                                close_fds=True,
350
 
                                                shell=True, cwd="/")
 
276
                logger.debug(u"Starting checker %r for %s",
 
277
                             command, self.name)
 
278
                self.checker = subprocess.\
 
279
                               Popen(command,
 
280
                                     close_fds=True, shell=True,
 
281
                                     cwd="/")
351
282
                self.checker_callback_tag = gobject.child_watch_add\
352
283
                                            (self.checker.pid,
353
284
                                             self.checker_callback)
354
 
            except OSError, error:
 
285
            except subprocess.OSError, error:
355
286
                logger.error(u"Failed to start subprocess: %s",
356
287
                             error)
357
288
        # Re-run this periodically if run by gobject.timeout_add
361
292
        if self.checker_callback_tag:
362
293
            gobject.source_remove(self.checker_callback_tag)
363
294
            self.checker_callback_tag = None
364
 
        if getattr(self, "checker", None) is None:
 
295
        if not hasattr(self, "checker") or self.checker is None:
365
296
            return
366
 
        logger.debug(u"Stopping checker for %(name)s", vars(self))
 
297
        logger.debug("Stopping checker for %(name)s", vars(self))
367
298
        try:
368
299
            os.kill(self.checker.pid, signal.SIGTERM)
369
300
            #os.sleep(0.5)
370
301
            #if self.checker.poll() is None:
371
302
            #    os.kill(self.checker.pid, signal.SIGKILL)
372
303
        except OSError, error:
373
 
            if error.errno != errno.ESRCH: # No such process
 
304
            if error.errno != errno.ESRCH:
374
305
                raise
375
306
        self.checker = None
376
 
    def still_valid(self):
 
307
    def still_valid(self, now=None):
377
308
        """Has the timeout not yet passed for this client?"""
378
 
        now = datetime.datetime.now()
379
 
        if self.last_checked_ok is None:
 
309
        if now is None:
 
310
            now = datetime.datetime.now()
 
311
        if self.last_seen is None:
380
312
            return now < (self.created + self.timeout)
381
313
        else:
382
 
            return now < (self.last_checked_ok + self.timeout)
 
314
            return now < (self.last_seen + self.timeout)
383
315
 
384
316
 
385
317
def peer_certificate(session):
401
333
 
402
334
def fingerprint(openpgp):
403
335
    "Convert an OpenPGP bytestring to a hexdigit fingerprint string"
 
336
    # New empty GnuTLS certificate
 
337
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
 
338
    gnutls.library.functions.gnutls_openpgp_crt_init\
 
339
        (ctypes.byref(crt))
404
340
    # New GnuTLS "datum" with the OpenPGP public key
405
341
    datum = gnutls.library.types.gnutls_datum_t\
406
342
        (ctypes.cast(ctypes.c_char_p(openpgp),
407
343
                     ctypes.POINTER(ctypes.c_ubyte)),
408
344
         ctypes.c_uint(len(openpgp)))
409
 
    # New empty GnuTLS certificate
410
 
    crt = gnutls.library.types.gnutls_openpgp_crt_t()
411
 
    gnutls.library.functions.gnutls_openpgp_crt_init\
412
 
        (ctypes.byref(crt))
413
345
    # Import the OpenPGP public key into the certificate
414
 
    gnutls.library.functions.gnutls_openpgp_crt_import\
415
 
                    (crt, ctypes.byref(datum),
416
 
                     gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
417
 
    # Verify the self signature in the key
418
 
    crtverify = ctypes.c_uint();
419
 
    gnutls.library.functions.gnutls_openpgp_crt_verify_self\
420
 
        (crt, 0, ctypes.byref(crtverify))
421
 
    if crtverify.value != 0:
422
 
        gnutls.library.functions.gnutls_openpgp_crt_deinit(crt)
423
 
        raise gnutls.errors.CertificateSecurityError("Verify failed")
 
346
    ret = gnutls.library.functions.gnutls_openpgp_crt_import\
 
347
        (crt,
 
348
         ctypes.byref(datum),
 
349
         gnutls.library.constants.GNUTLS_OPENPGP_FMT_RAW)
424
350
    # New buffer for the fingerprint
425
351
    buffer = ctypes.create_string_buffer(20)
426
352
    buffer_length = ctypes.c_size_t()
442
368
    Note: This will run in its own forked process."""
443
369
    
444
370
    def handle(self):
445
 
        logger.info(u"TCP connection from: %s",
 
371
        logger.debug(u"TCP connection from: %s",
446
372
                     unicode(self.client_address))
447
 
        session = gnutls.connection.ClientSession\
448
 
                  (self.request, gnutls.connection.X509Credentials())
449
 
        
450
 
        line = self.request.makefile().readline()
451
 
        logger.debug(u"Protocol version: %r", line)
452
 
        try:
453
 
            if int(line.strip().split()[0]) > 1:
454
 
                raise RuntimeError
455
 
        except (ValueError, IndexError, RuntimeError), error:
456
 
            logger.error(u"Unknown protocol version: %s", error)
457
 
            return
458
 
        
459
 
        # Note: gnutls.connection.X509Credentials is really a generic
460
 
        # GnuTLS certificate credentials object so long as no X.509
461
 
        # keys are added to it.  Therefore, we can use it here despite
462
 
        # using OpenPGP certificates.
 
373
        session = gnutls.connection.ClientSession(self.request,
 
374
                                                  gnutls.connection.\
 
375
                                                  X509Credentials())
463
376
        
464
377
        #priority = ':'.join(("NONE", "+VERS-TLS1.1", "+AES-256-CBC",
465
378
        #                "+SHA1", "+COMP-NULL", "+CTYPE-OPENPGP",
466
379
        #                "+DHE-DSS"))
467
 
        priority = "NORMAL"             # Fallback default, since this
468
 
                                        # MUST be set.
469
 
        if self.server.settings["priority"]:
470
 
            priority = self.server.settings["priority"]
 
380
        priority = "SECURE256"
 
381
        
471
382
        gnutls.library.functions.gnutls_priority_set_direct\
472
383
            (session._c_object, priority, None);
473
384
        
474
385
        try:
475
386
            session.handshake()
476
387
        except gnutls.errors.GNUTLSError, error:
477
 
            logger.warning(u"Handshake failed: %s", error)
 
388
            logger.debug(u"Handshake failed: %s", error)
478
389
            # Do not run session.bye() here: the session is not
479
390
            # established.  Just abandon the request.
480
391
            return
481
392
        try:
482
393
            fpr = fingerprint(peer_certificate(session))
483
394
        except (TypeError, gnutls.errors.GNUTLSError), error:
484
 
            logger.warning(u"Bad certificate: %s", error)
 
395
            logger.debug(u"Bad certificate: %s", error)
485
396
            session.bye()
486
397
            return
487
398
        logger.debug(u"Fingerprint: %s", fpr)
490
401
            if c.fingerprint == fpr:
491
402
                client = c
492
403
                break
493
 
        if not client:
494
 
            logger.warning(u"Client not found for fingerprint: %s",
495
 
                           fpr)
496
 
            session.bye()
497
 
            return
498
404
        # Have to check if client.still_valid(), since it is possible
499
405
        # that the client timed out while establishing the GnuTLS
500
406
        # session.
501
 
        if not client.still_valid():
502
 
            logger.warning(u"Client %(name)s is invalid",
503
 
                           vars(client))
 
407
        if (not client) or (not client.still_valid()):
 
408
            if client:
 
409
                logger.debug(u"Client %(name)s is invalid",
 
410
                             vars(client))
 
411
            else:
 
412
                logger.debug(u"Client not found for fingerprint: %s",
 
413
                             fpr)
504
414
            session.bye()
505
415
            return
506
416
        sent_size = 0
516
426
class IPv6_TCPServer(SocketServer.ForkingTCPServer, object):
517
427
    """IPv6 TCP server.  Accepts 'None' as address and/or port.
518
428
    Attributes:
519
 
        settings:       Server settings
 
429
        options:        Command line options
520
430
        clients:        Set() of Client objects
521
 
        enabled:        Boolean; whether this server is activated yet
522
431
    """
523
432
    address_family = socket.AF_INET6
524
433
    def __init__(self, *args, **kwargs):
525
 
        if "settings" in kwargs:
526
 
            self.settings = kwargs["settings"]
527
 
            del kwargs["settings"]
 
434
        if "options" in kwargs:
 
435
            self.options = kwargs["options"]
 
436
            del kwargs["options"]
528
437
        if "clients" in kwargs:
529
438
            self.clients = kwargs["clients"]
530
439
            del kwargs["clients"]
531
 
        self.enabled = False
532
440
        return super(type(self), self).__init__(*args, **kwargs)
533
441
    def server_bind(self):
534
442
        """This overrides the normal server_bind() function
535
443
        to bind to an interface if one was specified, and also NOT to
536
444
        bind to an address or port if they were not specified."""
537
 
        if self.settings["interface"]:
538
 
            # 25 is from /usr/include/asm-i486/socket.h
539
 
            SO_BINDTODEVICE = getattr(socket, "SO_BINDTODEVICE", 25)
 
445
        if self.options.interface:
 
446
            if not hasattr(socket, "SO_BINDTODEVICE"):
 
447
                # From /usr/include/asm-i486/socket.h
 
448
                socket.SO_BINDTODEVICE = 25
540
449
            try:
541
450
                self.socket.setsockopt(socket.SOL_SOCKET,
542
 
                                       SO_BINDTODEVICE,
543
 
                                       self.settings["interface"])
 
451
                                       socket.SO_BINDTODEVICE,
 
452
                                       self.options.interface)
544
453
            except socket.error, error:
545
454
                if error[0] == errno.EPERM:
546
 
                    logger.error(u"No permission to"
547
 
                                 u" bind to interface %s",
548
 
                                 self.settings["interface"])
 
455
                    logger.warning(u"No permission to"
 
456
                                   u" bind to interface %s",
 
457
                                   self.options.interface)
549
458
                else:
550
459
                    raise error
551
460
        # Only bind(2) the socket if we really need to.
554
463
                in6addr_any = "::"
555
464
                self.server_address = (in6addr_any,
556
465
                                       self.server_address[1])
557
 
            elif not self.server_address[1]:
 
466
            elif self.server_address[1] is None:
558
467
                self.server_address = (self.server_address[0],
559
468
                                       0)
560
 
#                 if self.settings["interface"]:
561
 
#                     self.server_address = (self.server_address[0],
562
 
#                                            0, # port
563
 
#                                            0, # flowinfo
564
 
#                                            if_nametoindex
565
 
#                                            (self.settings
566
 
#                                             ["interface"]))
567
469
            return super(type(self), self).server_bind()
568
 
    def server_activate(self):
569
 
        if self.enabled:
570
 
            return super(type(self), self).server_activate()
571
 
    def enable(self):
572
 
        self.enabled = True
573
470
 
574
471
 
575
472
def string_to_delta(interval):
585
482
    datetime.timedelta(1)
586
483
    >>> string_to_delta(u'1w')
587
484
    datetime.timedelta(7)
588
 
    >>> string_to_delta('5m 30s')
589
 
    datetime.timedelta(0, 330)
590
485
    """
591
 
    timevalue = datetime.timedelta(0)
592
 
    for s in interval.split():
593
 
        try:
594
 
            suffix=unicode(s[-1])
595
 
            value=int(s[:-1])
596
 
            if suffix == u"d":
597
 
                delta = datetime.timedelta(value)
598
 
            elif suffix == u"s":
599
 
                delta = datetime.timedelta(0, value)
600
 
            elif suffix == u"m":
601
 
                delta = datetime.timedelta(0, 0, 0, 0, value)
602
 
            elif suffix == u"h":
603
 
                delta = datetime.timedelta(0, 0, 0, 0, 0, value)
604
 
            elif suffix == u"w":
605
 
                delta = datetime.timedelta(0, 0, 0, 0, 0, 0, value)
606
 
            else:
607
 
                raise ValueError
608
 
        except (ValueError, IndexError):
 
486
    try:
 
487
        suffix=unicode(interval[-1])
 
488
        value=int(interval[:-1])
 
489
        if suffix == u"d":
 
490
            delta = datetime.timedelta(value)
 
491
        elif suffix == u"s":
 
492
            delta = datetime.timedelta(0, value)
 
493
        elif suffix == u"m":
 
494
            delta = datetime.timedelta(0, 0, 0, 0, value)
 
495
        elif suffix == u"h":
 
496
            delta = datetime.timedelta(0, 0, 0, 0, 0, value)
 
497
        elif suffix == u"w":
 
498
            delta = datetime.timedelta(0, 0, 0, 0, 0, 0, value)
 
499
        else:
609
500
            raise ValueError
610
 
        timevalue += delta
611
 
    return timevalue
 
501
    except (ValueError, IndexError):
 
502
        raise ValueError
 
503
    return delta
 
504
 
 
505
 
 
506
def add_service():
 
507
    """Derived from the Avahi example code"""
 
508
    global group, serviceName, serviceType, servicePort, serviceTXT, \
 
509
           domain, host
 
510
    if group is None:
 
511
        group = dbus.Interface(
 
512
                bus.get_object( avahi.DBUS_NAME,
 
513
                                server.EntryGroupNew()),
 
514
                avahi.DBUS_INTERFACE_ENTRY_GROUP)
 
515
        group.connect_to_signal('StateChanged',
 
516
                                entry_group_state_changed)
 
517
    logger.debug(u"Adding service '%s' of type '%s' ...",
 
518
                 serviceName, serviceType)
 
519
    
 
520
    group.AddService(
 
521
            serviceInterface,           # interface
 
522
            avahi.PROTO_INET6,          # protocol
 
523
            dbus.UInt32(0),             # flags
 
524
            serviceName, serviceType,
 
525
            domain, host,
 
526
            dbus.UInt16(servicePort),
 
527
            avahi.string_array_to_txt_array(serviceTXT))
 
528
    group.Commit()
 
529
 
 
530
 
 
531
def remove_service():
 
532
    """From the Avahi example code"""
 
533
    global group
 
534
    
 
535
    if not group is None:
 
536
        group.Reset()
612
537
 
613
538
 
614
539
def server_state_changed(state):
615
540
    """Derived from the Avahi example code"""
616
541
    if state == avahi.SERVER_COLLISION:
617
 
        logger.error(u"Zeroconf server name collision")
618
 
        service.remove()
 
542
        logger.warning(u"Server name collision")
 
543
        remove_service()
619
544
    elif state == avahi.SERVER_RUNNING:
620
 
        service.add()
 
545
        add_service()
621
546
 
622
547
 
623
548
def entry_group_state_changed(state, error):
624
549
    """Derived from the Avahi example code"""
625
 
    logger.debug(u"Avahi state change: %i", state)
 
550
    global serviceName, server, rename_count
 
551
    
 
552
    logger.debug(u"state change: %i", state)
626
553
    
627
554
    if state == avahi.ENTRY_GROUP_ESTABLISHED:
628
 
        logger.debug(u"Zeroconf service established.")
 
555
        logger.debug(u"Service established.")
629
556
    elif state == avahi.ENTRY_GROUP_COLLISION:
630
 
        logger.warning(u"Zeroconf service name collision.")
631
 
        service.rename()
 
557
        
 
558
        rename_count = rename_count - 1
 
559
        if rename_count > 0:
 
560
            name = server.GetAlternativeServiceName(name)
 
561
            logger.warning(u"Service name collision, "
 
562
                           u"changing name to '%s' ...", name)
 
563
            remove_service()
 
564
            add_service()
 
565
            
 
566
        else:
 
567
            logger.error(u"No suitable service name found after %i"
 
568
                         u" retries, exiting.", n_rename)
 
569
            killme(1)
632
570
    elif state == avahi.ENTRY_GROUP_FAILURE:
633
 
        logger.critical(u"Avahi: Error in group state changed %s",
634
 
                        unicode(error))
635
 
        raise AvahiGroupError("State changed: %s", str(error))
 
571
        logger.error(u"Error in group state changed %s",
 
572
                     unicode(error))
 
573
        killme(1)
 
574
 
636
575
 
637
576
def if_nametoindex(interface):
638
 
    """Call the C function if_nametoindex(), or equivalent"""
639
 
    global if_nametoindex
 
577
    """Call the C function if_nametoindex()"""
640
578
    try:
641
 
        if "ctypes.util" not in sys.modules:
642
 
            import ctypes.util
643
 
        if_nametoindex = ctypes.cdll.LoadLibrary\
644
 
            (ctypes.util.find_library("c")).if_nametoindex
 
579
        libc = ctypes.cdll.LoadLibrary("libc.so.6")
 
580
        return libc.if_nametoindex(interface)
645
581
    except (OSError, AttributeError):
646
582
        if "struct" not in sys.modules:
647
583
            import struct
648
584
        if "fcntl" not in sys.modules:
649
585
            import fcntl
650
 
        def if_nametoindex(interface):
651
 
            "Get an interface index the hard way, i.e. using fcntl()"
652
 
            SIOCGIFINDEX = 0x8933  # From /usr/include/linux/sockios.h
653
 
            s = socket.socket()
654
 
            ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
655
 
                                struct.pack("16s16x", interface))
656
 
            s.close()
657
 
            interface_index = struct.unpack("I", ifreq[16:20])[0]
658
 
            return interface_index
659
 
    return if_nametoindex(interface)
660
 
 
661
 
 
662
 
def daemon(nochdir = False, noclose = False):
 
586
        SIOCGIFINDEX = 0x8933      # From /usr/include/linux/sockios.h
 
587
        s = socket.socket()
 
588
        ifreq = fcntl.ioctl(s, SIOCGIFINDEX,
 
589
                            struct.pack("16s16x", interface))
 
590
        s.close()
 
591
        interface_index = struct.unpack("I", ifreq[16:20])[0]
 
592
        return interface_index
 
593
 
 
594
 
 
595
def daemon(nochdir, noclose):
663
596
    """See daemon(3).  Standard BSD Unix function.
664
597
    This should really exist as os.daemon, but it doesn't (yet)."""
665
598
    if os.fork():
667
600
    os.setsid()
668
601
    if not nochdir:
669
602
        os.chdir("/")
670
 
    if os.fork():
671
 
        sys.exit()
672
603
    if not noclose:
673
604
        # Close all standard open file descriptors
674
 
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
 
605
        null = os.open("/dev/null", os.O_NOCTTY | os.O_RDWR)
675
606
        if not stat.S_ISCHR(os.fstat(null).st_mode):
676
607
            raise OSError(errno.ENODEV,
677
608
                          "/dev/null not a character device")
682
613
            os.close(null)
683
614
 
684
615
 
 
616
def killme(status = 0):
 
617
    logger.debug("Stopping server with exit status %d", status)
 
618
    exitstatus = status
 
619
    if main_loop_started:
 
620
        main_loop.quit()
 
621
    else:
 
622
        sys.exit(status)
 
623
 
 
624
 
685
625
def main():
 
626
    global exitstatus
 
627
    exitstatus = 0
686
628
    global main_loop_started
687
629
    main_loop_started = False
688
630
    
689
 
    parser = OptionParser(version = "%%prog %s" % version)
 
631
    parser = OptionParser()
690
632
    parser.add_option("-i", "--interface", type="string",
691
 
                      metavar="IF", help="Bind to interface IF")
692
 
    parser.add_option("-a", "--address", type="string",
 
633
                      default=None, metavar="IF",
 
634
                      help="Bind to interface IF")
 
635
    parser.add_option("-a", "--address", type="string", default=None,
693
636
                      help="Address to listen for requests on")
694
 
    parser.add_option("-p", "--port", type="int",
 
637
    parser.add_option("-p", "--port", type="int", default=None,
695
638
                      help="Port number to receive requests on")
 
639
    parser.add_option("--timeout", type="string", # Parsed later
 
640
                      default="1h",
 
641
                      help="Amount of downtime allowed for clients")
 
642
    parser.add_option("--interval", type="string", # Parsed later
 
643
                      default="5m",
 
644
                      help="How often to check that a client is up")
696
645
    parser.add_option("--check", action="store_true", default=False,
697
646
                      help="Run self-test")
698
 
    parser.add_option("--debug", action="store_true",
699
 
                      help="Debug mode; run in foreground and log to"
700
 
                      " terminal")
701
 
    parser.add_option("--priority", type="string", help="GnuTLS"
702
 
                      " priority string (see GnuTLS documentation)")
703
 
    parser.add_option("--servicename", type="string", metavar="NAME",
704
 
                      help="Zeroconf service name")
705
 
    parser.add_option("--configdir", type="string",
706
 
                      default="/etc/mandos", metavar="DIR",
707
 
                      help="Directory to search for configuration"
708
 
                      " files")
 
647
    parser.add_option("--debug", action="store_true", default=False,
 
648
                      help="Debug mode")
709
649
    (options, args) = parser.parse_args()
710
650
    
711
651
    if options.check:
713
653
        doctest.testmod()
714
654
        sys.exit()
715
655
    
716
 
    # Default values for config file for server-global settings
717
 
    server_defaults = { "interface": "",
718
 
                        "address": "",
719
 
                        "port": "",
720
 
                        "debug": "False",
721
 
                        "priority":
722
 
                        "SECURE256:!CTYPE-X.509:+CTYPE-OPENPGP",
723
 
                        "servicename": "Mandos",
724
 
                        }
725
 
    
726
 
    # Parse config file for server-global settings
727
 
    server_config = ConfigParser.SafeConfigParser(server_defaults)
728
 
    del server_defaults
729
 
    server_config.read(os.path.join(options.configdir, "mandos.conf"))
730
 
    # Convert the SafeConfigParser object to a dict
731
 
    server_settings = server_config.defaults()
732
 
    # Use getboolean on the boolean config option
733
 
    server_settings["debug"] = server_config.getboolean\
734
 
                               ("DEFAULT", "debug")
735
 
    del server_config
736
 
    
737
 
    # Override the settings from the config file with command line
738
 
    # options, if set.
739
 
    for option in ("interface", "address", "port", "debug",
740
 
                   "priority", "servicename", "configdir"):
741
 
        value = getattr(options, option)
742
 
        if value is not None:
743
 
            server_settings[option] = value
744
 
    del options
745
 
    # Now we have our good server settings in "server_settings"
746
 
    
747
 
    debug = server_settings["debug"]
748
 
    
749
 
    if not debug:
750
 
        syslogger.setLevel(logging.WARNING)
751
 
        console.setLevel(logging.WARNING)
752
 
    
753
 
    if server_settings["servicename"] != "Mandos":
754
 
        syslogger.setFormatter(logging.Formatter\
755
 
                               ('Mandos (%s): %%(levelname)s:'
756
 
                                ' %%(message)s'
757
 
                                % server_settings["servicename"]))
758
 
    
759
 
    # Parse config file with clients
760
 
    client_defaults = { "timeout": "1h",
761
 
                        "interval": "5m",
762
 
                        "checker": "fping -q -- %(host)s",
763
 
                        "host": "",
764
 
                        }
765
 
    client_config = ConfigParser.SafeConfigParser(client_defaults)
766
 
    client_config.read(os.path.join(server_settings["configdir"],
767
 
                                    "clients.conf"))
768
 
    
769
 
    clients = Set()
770
 
    tcp_server = IPv6_TCPServer((server_settings["address"],
771
 
                                 server_settings["port"]),
772
 
                                tcp_handler,
773
 
                                settings=server_settings,
774
 
                                clients=clients)
775
 
    pidfilename = "/var/run/mandos.pid"
776
 
    try:
777
 
        pidfile = open(pidfilename, "w")
778
 
    except IOError, error:
779
 
        logger.error("Could not open file %r", pidfilename)
780
 
    
781
 
    uid = 65534
782
 
    gid = 65534
783
 
    try:
784
 
        uid = pwd.getpwnam("mandos").pw_uid
785
 
    except KeyError:
786
 
        try:
787
 
            uid = pwd.getpwnam("nobody").pw_uid
788
 
        except KeyError:
789
 
            pass
790
 
    try:
791
 
        gid = pwd.getpwnam("mandos").pw_gid
792
 
    except KeyError:
793
 
        try:
794
 
            gid = pwd.getpwnam("nogroup").pw_gid
795
 
        except KeyError:
796
 
            pass
797
 
    try:
798
 
        os.setuid(uid)
799
 
        os.setgid(gid)
800
 
    except OSError, error:
801
 
        if error[0] != errno.EPERM:
802
 
            raise error
803
 
    
804
 
    global service
805
 
    service = AvahiService(name = server_settings["servicename"],
806
 
                           type = "_mandos._tcp", );
807
 
    if server_settings["interface"]:
808
 
        service.interface = if_nametoindex\
809
 
                            (server_settings["interface"])
 
656
    # Parse the time arguments
 
657
    try:
 
658
        options.timeout = string_to_delta(options.timeout)
 
659
    except ValueError:
 
660
        parser.error("option --timeout: Unparseable time")
 
661
    try:
 
662
        options.interval = string_to_delta(options.interval)
 
663
    except ValueError:
 
664
        parser.error("option --interval: Unparseable time")
 
665
    
 
666
    # Parse config file
 
667
    defaults = { "checker": "fping -q -- %%(fqdn)s" }
 
668
    client_config = ConfigParser.SafeConfigParser(defaults)
 
669
    #client_config.readfp(open("global.conf"), "global.conf")
 
670
    client_config.read("mandos-clients.conf")
810
671
    
811
672
    global main_loop
812
673
    global bus
815
676
    DBusGMainLoop(set_as_default=True )
816
677
    main_loop = gobject.MainLoop()
817
678
    bus = dbus.SystemBus()
818
 
    server = dbus.Interface(bus.get_object(avahi.DBUS_NAME,
819
 
                                           avahi.DBUS_PATH_SERVER),
820
 
                            avahi.DBUS_INTERFACE_SERVER)
 
679
    server = dbus.Interface(
 
680
            bus.get_object( avahi.DBUS_NAME, avahi.DBUS_PATH_SERVER ),
 
681
            avahi.DBUS_INTERFACE_SERVER )
821
682
    # End of Avahi example code
822
683
    
 
684
    debug = options.debug
 
685
    
 
686
    if debug:
 
687
        console = logging.StreamHandler()
 
688
        # console.setLevel(logging.DEBUG)
 
689
        console.setFormatter(logging.Formatter\
 
690
                             ('%(levelname)s: %(message)s'))
 
691
        logger.addHandler(console)
 
692
        del console
 
693
    
 
694
    clients = Set()
823
695
    def remove_from_clients(client):
824
696
        clients.remove(client)
825
697
        if not clients:
826
 
            logger.critical(u"No clients left, exiting")
827
 
            sys.exit()
 
698
            logger.debug(u"No clients left, exiting")
 
699
            killme()
828
700
    
829
 
    clients.update(Set(Client(name = section,
 
701
    clients.update(Set(Client(name=section, options=options,
830
702
                              stop_hook = remove_from_clients,
831
 
                              config
832
 
                              = dict(client_config.items(section)))
 
703
                              **(dict(client_config\
 
704
                                      .items(section))))
833
705
                       for section in client_config.sections()))
834
 
    if not clients:
835
 
        logger.critical(u"No clients defined")
836
 
        sys.exit(1)
837
 
    
838
 
    if debug:
839
 
        # Redirect stdin so all checkers get /dev/null
840
 
        null = os.open(os.path.devnull, os.O_NOCTTY | os.O_RDWR)
841
 
        os.dup2(null, sys.stdin.fileno())
842
 
        if null > 2:
843
 
            os.close(null)
844
 
    else:
845
 
        # No console logging
846
 
        logger.removeHandler(console)
847
 
        # Close all input and output, do double fork, etc.
848
 
        daemon()
849
 
    
850
 
    try:
851
 
        pid = os.getpid()
852
 
        pidfile.write(str(pid) + "\n")
853
 
        pidfile.close()
854
 
        del pidfile
855
 
    except IOError, err:
856
 
        logger.error(u"Could not write to file %r with PID %d",
857
 
                     pidfilename, pid)
858
 
    except NameError:
859
 
        # "pidfile" was never created
860
 
        pass
861
 
    del pidfilename
 
706
    
 
707
    if not debug:
 
708
        daemon(False, False)
862
709
    
863
710
    def cleanup():
864
711
        "Cleanup function; run on exit"
878
725
    
879
726
    if not debug:
880
727
        signal.signal(signal.SIGINT, signal.SIG_IGN)
881
 
    signal.signal(signal.SIGHUP, lambda signum, frame: sys.exit())
882
 
    signal.signal(signal.SIGTERM, lambda signum, frame: sys.exit())
 
728
    signal.signal(signal.SIGHUP, lambda signum, frame: killme())
 
729
    signal.signal(signal.SIGTERM, lambda signum, frame: killme())
883
730
    
884
731
    for client in clients:
885
732
        client.start()
886
733
    
887
 
    tcp_server.enable()
888
 
    tcp_server.server_activate()
889
 
    
890
 
    # Find out what port we got
891
 
    service.port = tcp_server.socket.getsockname()[1]
892
 
    logger.info(u"Now listening on address %r, port %d, flowinfo %d,"
893
 
                u" scope_id %d" % tcp_server.socket.getsockname())
894
 
    
895
 
    #service.interface = tcp_server.socket.getsockname()[3]
896
 
    
897
 
    try:
898
 
        # From the Avahi example code
899
 
        server.connect_to_signal("StateChanged", server_state_changed)
900
 
        try:
901
 
            server_state_changed(server.GetState())
902
 
        except dbus.exceptions.DBusException, error:
903
 
            logger.critical(u"DBusException: %s", error)
904
 
            sys.exit(1)
905
 
        # End of Avahi example code
906
 
        
907
 
        gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,
908
 
                             lambda *args, **kwargs:
909
 
                             tcp_server.handle_request\
910
 
                             (*args[2:], **kwargs) or True)
911
 
        
912
 
        logger.debug(u"Starting main loop")
 
734
    tcp_server = IPv6_TCPServer((options.address, options.port),
 
735
                                tcp_handler,
 
736
                                options=options,
 
737
                                clients=clients)
 
738
    # Find out what random port we got
 
739
    global servicePort
 
740
    servicePort = tcp_server.socket.getsockname()[1]
 
741
    logger.debug(u"Now listening on port %d", servicePort)
 
742
    
 
743
    if options.interface is not None:
 
744
        global serviceInterface
 
745
        serviceInterface = if_nametoindex(options.interface)
 
746
    
 
747
    # From the Avahi example code
 
748
    server.connect_to_signal("StateChanged", server_state_changed)
 
749
    try:
 
750
        server_state_changed(server.GetState())
 
751
    except dbus.exceptions.DBusException, error:
 
752
        logger.critical(u"DBusException: %s", error)
 
753
        killme(1)
 
754
    # End of Avahi example code
 
755
    
 
756
    gobject.io_add_watch(tcp_server.fileno(), gobject.IO_IN,
 
757
                         lambda *args, **kwargs:
 
758
                         tcp_server.handle_request(*args[2:],
 
759
                                                   **kwargs) or True)
 
760
    try:
 
761
        logger.debug("Starting main loop")
913
762
        main_loop_started = True
914
763
        main_loop.run()
915
 
    except AvahiError, error:
916
 
        logger.critical(u"AvahiError: %s" + unicode(error))
917
 
        sys.exit(1)
918
764
    except KeyboardInterrupt:
919
765
        if debug:
920
766
            print
 
767
    
 
768
    sys.exit(exitstatus)
921
769
 
922
770
if __name__ == '__main__':
923
771
    main()